Nordette as ECP, Help!

Patient: My girlfriend and I had unprotected sex. I ejaculated inside her March 30 around 5 pm. She took Nordette at around 7:30 am the following morning. What time should she drink pills again? How many pills? When should she stop drinking Nordette? Her period is coming this April 10 or around that week. Thank you for your help.

Symptoms: Unprotected sex